Cinematographer
Aus DoP-Perspektive ist dieses Element essentiell für die visuelle Gestaltung. Es ermöglicht mir die gewünschte Farbstimmung und das ästhetische Bild konsistent umzusetzen.
Spectral measurement instrument that captures light spectrum and calculates color temperature and color rendering indices (CRI, TLCI, TM-30, SSI) for set lighting.
Overview
A spectrometer in the film and TV industry is a light measuring device that captures not only the brightness but the entire spectral profile of a light source. Instead of a single value, it breaks down light across the visible wavelength range and calculates color temperature and a series of color rendering indices from it. This distinguishes it from a classic color temperature meter (Color Meter), which only provides Kelvin values and filter correction.
The de facto standard on set is the Sekonic C-800 (or its US variant C-800-U). It serves gaffers, lighting technicians, and the camera department to measure LED, HMI, fluorescent, and daylight sources, to match them with each other, and to set them to a desired color temperature before shooting.
Functionality and Indices
A spectrometer captures incident light via an optical sensor and measures the intensity distribution per wavelength. From this spectral curve, the following indices, among others, are derived:
- CCT – Correlated Color Temperature (in Kelvin)
- CRI – Color Rendering Index, color rendering relative to the human eye
- TLCI – Television Lighting Consistency Index, relative to a camera sensor characteristic
- TM-30 – Modern IES metric (Rf/Rg) for evaluating color fidelity and saturation
- SSI – Spectral Similarity Index from the Academy Sci-Tech Council, for matching a source against a reference
Since the spectrum is directly visible, especially with LED sources, individual spectral peaks or gaps can be detected that remain hidden with a pure Kelvin value.
Technical Data (Sekonic C-800)
| Parameter | Value |
|---|---|
| Wavelength Range | 380–780 nm |
| Sensor | CMOS linear image sensor |
| Color Temperature (Continuous Light) | 1,600–40,000 K |
| Color Temperature (Flash) | 2,500–40,000 K |
| Illuminance (Continuous Light) | 1–200,000 lx |
| Color Metrics | CRI, TLCI, TLMF, TM-30-18, SSI |
| Display | 4.3" Touch LCD |
| Measuring Head | 270° swivel |
| Weight | approx. 0.23 kg |
Use on Set
Before shooting, the gaffer uses the spectrometer to check if all lights used deliver the same color temperature and comparable color rendering. Especially when mixing different LED brands or combining LED with HMI and daylight, the device helps to detect visible color deviations (green/magenta cast, off-key skin tones) on set and to correct them using filters or fixture control. This reduces color correction in post-production and ensures consistent skin tones between shots.
From the crafts
Perspectives
Producer
Diese professionelle Lösung erhöht die Produktionseffizienz und reduziert Post-Production-Anforderungen. Sie ermöglicht flexible, schnelle Anpassungen während des Drehs.
Gaffer
Als Gaffer ist dies ein unverzichtbares Werkzeug meines täglichen Handwerkszeugs. Es ermöglicht mir professionelle Lichtkontrolle und schnelle Anpassungen auf Set, was Zeit spart und Qualität sichert.
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Related terms
Test your knowledge
Quiz
1. Zu welchem Department gehört „Spektrometer"?
2. Wie viele verschiedene Fachperspektiven bietet dieser Eintrag?